Dipole moment of acetylcholine and its relevance to the chemical synaptic transmission

Insulin-lecithin interaction in non-aqueous solvents and its change after application of a static electric field

The interaction between dipalmitoyl lecithin and egg lecithin with insulin was studied in a non-aqueous solvent such as dioxane-chloroform (1:1) by dielectric constant measurements and absorption spectra. The electrostatic character of the interaction results from the dielectric measurements and the effect of an external application of a static electric field (F = 30 kV/cm) is apparently related to the strength of such an interaction. The different strength of interaction of insulin with the two types of lecithins results also from experiments with a two-phase system.

Electric hysteresis and mitochondrial incorporation of RNAs from different sources

The paper reports the characteristics of four different RNAs from yeast, Torula and calf thymus of molecular weight ranging between 15,000 and 30,000. The gel-filtration behaviour with aqueous and partially qqueous solvents is studied together with the response of the four RNAs to static electric fields of strength ranging between 20 and 35 kV/cm. The relationship between molecular weight and extent of electric hysteresis is linear for all RNAs, while tRNA slightly deviates from such a relationship. The ability of the RNAs to permeate biological mebranes or bind membrane components such as lecithins is studied with rat liver mitochondria and a two-phase system with egg lecithin dissolved in the organic phase and RNA in the aqueous one. There is no apparent relationship between molecular weight of the RNAs and their ability to interact with biological membranes.

Dielectric increment of low molecular weight RNA in dioxane after application of static electric fields

A soluble RNA with a molecular weight between 15 000 and 23 000 was extracted from calf thymus and chromatographically purified. The RNA was slightly soluble in doxane (approx. 2.5 mug/ml) and RNA-dioxane solutions were used to fill a cell (452.02 pF capacitance) to which static electric fields of variable strength were applied. The dielectric permittivity of the solutions was measured at a fixed time interval after the application of the electric field. The RNA solutions showed a dielectric increment proportional to the strength of the applied field and to the RNA concentration. The existence of a hystersis effect was proven and the effect of the electric field on the RNA molecule might be related to a dielectric saturation phenomenon parallel to long-term changes of the molecule.